chipguy, your Linux point misses an important consideration: These leaders (IBM, HPQ and Dell) have not had Opteron as an offering until recently, and not yet in the types of quantities that they need. So discussing whether Xeon is preferred as a Linux platform over a time period when Opteron is not available is stacking the deck a bit.
The embracing of Opteron by 'Linux hackers' has to do with making product going foward. If there were no 64-bit Linux implementations for Opteron then there would be no market. So while "core kernel hackers" do not purchase many systems, they are the vanguard so that the sales leaders can start offering systems based on Opteron.
Soon system vendors will have to decide whether they want to offer high performance, competitively priced 64-bit Linux systems. If the leaders want such offerings then Opteron is the only game in town.
That is the significance of systems designed for "core kernel hackers".
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